This invention relates to glass forming machines and, in particular, to the parison or blank forming mechanism on the I.S. type of glass forming machine shown in the Ingle U.S. Pat. No. 1,911,119. In this patent, a glass forming charge is delivered to a parison mold at a parison molding station where the charge is shaped by settle blow and counterblowing the glass at the station to form a parison. The parison thereafter is inverted and transferred to a blow molding station where it is blown into its final shape.
Where a plurality of charges are to be delivered simultaneously to a plurality of parison molds at the parison molding station, considerable difficulty is encountered in providing sufficient clearance so that large diameter articles can be produced on a machine that basically has the same overall dimension as the above referred to conventional machine. Prior U.S. Pat. No. 3,721,545 to Irwin, of common assignee with present application, discloses a triple cavity glass forming apparatus. In the apparatus disclosed in U.S. Pat. No. 3,721,545, the distance from the mold arm hinge post 27 to the center of the neck mold invert arm axis, limits the mechanism to a triple gob glass forming machine. To increase the number of mold cavities provided on the basic machine would require a major expansion of the machine base and thus affect the entire layout of a glass container manufacturing plant.
The mechanism for opening and closing the parison molds, and the manner in which they are mounted on the arms for supporting them, is a significant arrangement in the present invention, and it is an object of the present invention to provide apparatus which will give equal closing forces on all of the four side-by-side parison mold haves, with the clamping of the parison molds in their closed position being carried out through the operation of existing crank arm mechanism on the conventional or existing I.S. machines.
It is a further object of this invention to provide apparatus for operation of the molds in which the mold arms are designed, such that they give greater closing forces on the long arms necessary to support four parison molds.